Schiff base and metal bisazomethine metal chelate

ABSTRACT

Novel Schiff bases are prepared by condensation of phenanthrene9,10-diamines with o-hydroxy aldehydes. The bases can be chelated with metals to form compounds useful as yellow pigments.

United States Patent 1191 Dhaliwal Related US. Application Data [62] Division of Ser. No. 313,359, Dec. 8, 1972.

52 US. (:1. 260/240 G; 260/429 (3 51 1111. C1. 0071) 215/20; C07C 199/10 [58] Field of Search 260/240 G, 429 C References Cited 1 UNITED STATES PATENTS 3,290,299 12/1966 Kieminsetal. 260/240G 3,441,578 4/1969 13011161111- 260/429CUX 3,687,991 8/1972 Gaeng etal 260/429c Dec. 23, 1975 2/1975 Inman et al. 260/429 C X OTHER PUBLICATIONS C. S. -Marvel et al. Heat Stability Studies on Chelates from Schiff Bases of Salicylaldehyde Derivatives Reprint Jun. J.A.C.S. 7926000, (1957). MacDennott, The Methylation of Basic Nitrogens in the Periphery of Meta'l(l1)Complexes, in Ausl, J. Chem. 1966, 19 2389-2392.

Birodan et al., Niobium(V)Complexes with Aromatic Schifi Bases in J. of the Less-Common Metals 26(1972), 355-359.

Primary Examiner-Allen B. Curtis ABSTRACT Novel Schifi bases are prepared by condensation of phenanthrene-9,IO-diamines with o-hydroxy aldehydes. The bases can be chelated with metals to form compounds useful as yellow pigments.

3 Claims, No Drawings SCHIFF BASE AND METAL BISAZOMETHINE METAL CHELAT E CROSS-REFERENCE TO mm!) APPLICATION This application is a division of application Ser. No. 313,359, filed Dec. 8, 1972.

BACKGROUND OF THE INVENTION Although a number of lightfast organic pigments have been developed in the blue to green color range, as exemplified by the phthalocyanines, and in the red to violet range, as exemplified by the quinacridones, there has been much less success with the development of such pigments in the yellow range. The present invention is directed to the production of novel yellow organic pigments.

SUMMARY OF THE INVENTION cording to the following reaction:

O u NH 0-H I 2 .r' 1 ll: e I l NH 2 a l D t 3W, D,- N I H u 0 p n 1 wherein D, represents the atoms necessary to complete a phenanthrene nucleus having the indicated nitrogen atoms attached to the 9,10-positions and D represents the atoms necessary to complete a nucleus of the formula:

wherein X is chlorine or bromine.

The metal chelate derivatives have the formula:

wherein Me is nickel, cobalt or copper and D, and D are as given before.

For the preparation of the Schiff bases and the chelates of the invention, phenanthrene-9,lO-diamines of the formula:

wherein R is hydrogen, chlorine or bromine, are preferred. Other substituents may be present on the phenanthrene moiety, however, for example, lower alkyl radicals such as methyl and ethyl, and alkoxy radicals such as methoxy.

The o-hydroxy aldehydes that may be employed include salicyl aldehyde; 3,5-dibromoand 3,5- dichlorosalicylaldehyde; 2,4dihydroxy-3-formylquinoline; and 2-hydroxy-l-naphthaldehyde. The preferred compound is 2,4-dihydroxy-3-formylquinoline which, when condensed with phenanthrene-9,lO-diamine and chelated yields a compound of the formula:

R H I ll N N/ ll 0 R wherein each R is hydrogen.

The Schiff bases of this invention are produced by condensing two moles of the o-hydroxy aldehyde with one mole of phenanthrene-9,lO-diamine or a substituted derivative of the latter. The Schiff base is further reacted with a nickel, cobalt or copper salt, such as for example nickel acetate, to give a highly insoluble reddish-yellow compound having exceptional lightfastness and other valuable pigmentary properties, i.e., to give the chelate.

The condensation of the o-hydroxy aldehyde with the phenanthrene-9,lO-diamine can be carried out in a variety of polar solvents. It is found that the reaction proceeds readily in acidic aqueous medium (pH 3-5), butanol, ethanol, and dimethylformamide. However, if desired, other solvents such as, for example, propanol, ethylene glycol or the like, may be used with equal success.

The metal complexes can be conveniently formed by reacting the Schiff base with a metal salt of an organic acid in suspension in a high-boiling solvent such as dimethylformamide, dimethylacetamide, dimethylsulfoxide, tetramethylene sulfone and the like. Although for purposes of illustration nickel acetate is the metal salt used and is preferred, salts of the metals cobalt or copper may be substituted. Salts other than acetates can be used provided they are sufficiently soluble in the solvent used in carrying out the chelation reaction. Since the condensation to form the Schiff base can also be carried out in a high-boiling polar solvent such as dimethylformamide or one of the other solvents listed above, the formation of both the Schiff base and the metal complex can be carried out in succession in the same reaction medium without isolation of the Schiff base intermediate.

To illustrate in detail the preparation of the compounds of the invention, the following examples are 4 EXAMPLE I A. Synthesis of Schiff base from 2,4-dihydroxy-3-formylquinoline and phenanthrene-9, l O-diamine Ten grams of phenanthrene-9,lO-diamine and 21.5 grams of 3,4-dihydroxy 3-formylquinoline are refluxed in 1800 ml butanol for 5 hours. The slurry is filtered hot and the presscake washed with alcohol and dried. The bright yellow Schiff base product weighs 22.5 grams.

. B. Formation of nickel chelate washed and dried. Thirteen and four-tenths grams of a red-shade yellow product are obtained. Upon analysis the following are the results:

Calculated for C H N O Ni Found Ni= 9.71 9.84 N 9.22 9.03 C =67.2l 66.24 H 3.29 3.37

This analysis indicates the compound to be the chelate of the structural formula given as (V), above, wherein Me is nickel and each R is hydrogen.

The chelate is reddish-yellow in color and is found to possess outstanding outdoor durability when used as a pigment.

EXAMPLE 2 A. Synthesis of 3 ,6-dichloro-phenanthrene-9, l O-diamine dihydrochloride In this synthesis 45.0 grams of 3,6-dichlorophenanthrene-9,l0-quinone, 62.5-grams barium carbonate, and 56.5 grams hydroxylamine hydrochloride are heated in 4000 ml ethyl alcohol at reflux for 5 hours. The slurry is filtered hot and the presscake washed with alcohol. The filtrate is concentrated by evaporation to half its volume, cooled to C. and 260 grams stannous chloride dissolved in 1200 ml concentrated hydrochloric acid is added over a 30 minute period, while maintaining the temperature below C. The slurry is stirred for an additional one-half hour period while maintaining the temperature at 70 to 80C., cooled to room temperature and filtered.

The presscake is washed first with concentrated hydrochloric acid, then with water, and dried at room temperature. The yield of white solid is 38.5 grams.

B. Synthesis of Schiff base from 2,4-dihydroxy-3-formylquinoline and the diamine of A Thirty-eight'and one-half grams of the product of A, and 46.8 grams of 2,4-dihydroxy-3-formylquinoline are heated in 4000 ml of butanol at reflux for 5 hours. The hot slurry is filtered, the presscake washed with ethanol anddried.

C. Formation of nickel chelate Thirty grams of the bright yellow Schiff base as prepared in B and 20.0grarns of nickel acetate tetrahydrate are heated under reflux in 3000 ml dimethylformamide for four hours. The slurry is filtered hot and the presscake washed free of nickel salts and dried. The product weighs 24.5 grams.

The 24.5 grams of product of C are pulverized and extracted with boiling dimethylformamide for 25 minutes, filtered hot, and the presscake washed until free of nickel salts and dried. A yield of 23.0 grams of a red-shade yellow product is obtained. Upon analysis, the following results are obtained:

Calculated for c a cuivpmi Found Ni= 8.60 8.89 8.29 8.11 C =61.48- 58.19 H 2.67 2.72 Cl=10.51 10.0

This analysis shows that the chelate'has a, structure corresponding to that of formula (V); above, wherein Me is nickel and each R is chlorine.

' EXAMPLE 3 Afsyhthesis of 3 ,6-dibrorno-phenanthrene-9,10-diamine dihydrochloride Forty-six grams of 3,6-dibromo-phenanthrene-9,10-

quinojne,:56.5 gramsz-of hydroxylamine hydrochloride and 62.5 grams of barium carbon-ateare heated at refluxin 2600 =mlethano1 for hours i Theslurry is filtered hot and the presscake washed with alcohol. The filtrate is heated to 70C. and 250 grams of stannous chloride dissolved in 1000 ml of concentrated hydrochloric acid is added over a 20 minute period with the temperature held at 80C. The slurry is cooled to room temperature over a 2 hour period and filtered, washed first with hydrochloric acid, and then with water, and dried. The product weighs 52.0 grams.

B. Synthesis of Schiff base from 2,4-dihydroxy-3-formylquion1ine and the diamine of A To carry out the reaction, 26.0 grams of the product obtained in step A and 31.2 grams of 2,4-dihydroxy-3- formylquinoline are heated at reflux for 5 hours in 3000 ml of butanol. The slurry is filtered hot and the presscake washed with alcohol and dried. The yield of product is 40.0 grams.

C. Formation of nickel chelate iamide, 2.3 grams nickel acetate tetrahydrate and 3.0

Calculated for C l-[ Br' N 0 Ni Found Ni= 7.59 7.43 N 7.33 7.14 C =53.40 52.07 H 2.35 2.48 Br=20.95 18.9

This analysis shows the chelate has a structure corresponding to that of formula (V), above, wherein Me is nickel and each R is bromine.

EXAMPLE 4 A. Synthesis of Schiff base from 2-hydroxy- 1 -naphthaldehyde and phenanthrene-9,10-diamine Calculated for CQ H MO, Found C 83.72 82.04 H 4.65 4.59 N 5.42 5.84

B. Formation of nickel chelate One gram of the product of A and 0.6 gram of nickel acetate tetrahydrate are heated in 100 ml of dimethylformamide at reflux for 4 hours. The slurry is filtered hot, washed, successively'with alcohol, water, and alcohol,.'and dried at C. The yield of chelate is 0.99 g am. n. i f I EXAMPLE 5 Preparation of the chelate of Example 1 without isolation of the Schiff base To carry out the reaction, 400 ml of dimethylformgrams 2,4-dihydroxy-3-formy1quino1ine are heated at reflux for 1 hour. After 1 hour, 2.0 grams phenanthrene-9,10-diamine dihydrochloride is added, and the reflux continued for an additional 3 and 1% hours. lmmediately upon addition of the phenanthrene-9,10-diamine dihydrochloride a reddish-yellow solid precipitates out of solution. At the end of the reflux period, the slurry is filtered hot, washed with alcohol, then with water and alcohol, and dried at C. The yield of the product is 2.2 grams.

EXAMPLE 6 Preparation of the chelate from 3 ,5 -dibromosalicylaldehyde, phenanthrene-9,lO-diamine dihydrochloride and nickel acetate For this preparation, 6 grams of nickel acetate tetrahydrate, and 10 grams of 3,5-dibromosalicy1aldehyde are refluxed for 2 hours in 200 ml dimethylformamide. At the end of this time, 5 grams of phenanthrene-9, 10- diamine dihydrochloride are added and the refluxing is continued for two hours. The hot slurry is then filtered,

the precipitate washed successively with alcohol, water, and alcohol, and dried at 60C. The yield of chelate is 5.4 grams.

For C H N O Br Ni, analysis shows:

Found Calculated Ni= 7.0l 7.35 N 3.65 3.55 C =44 42.75 H 1.95 1.77 Br=37.3 40.6

This example shows the formation of the tetrabromosubstituted chelate. The corresponding chlorosubstituted chelate can be prepared by simple molar substitution of 3,5-dichlorosalicylaldehyde for 3,5- dibromosalicylaldehyde. 4

What is claimed'is:

wherein D represents the atoms necessary to complete a phenanthrene nucleus having the indicated nitrogen atoms attached to the 9,10-positions and D represents the atoms necessary to complete a nucleus of the formula:

2. A metal chelate of structural formula:

2s v O 5 herein Me is nickel, cobalt or copper and R is hydroand each R is hydrogen. k 

1. A SCHIFF BASE OF STRUCTURAL FORMULA:
 2. A metal chelate of structural formula:
 3. A metal chelate of claim 2 wherein Me is nickel and each R is hydrogen. 